A knoll rock pile sites in Ashland, MA - part 2

As I approached this knoll I could see there was something interesting about to appear. I took a number of pictures here and in the vicinity; including rock piles with one quartz "blaze", and some others which were interesting to me. Here are some "blazed piles"
Here is another and a detail:
And another, with detail:
I am going to be claiming that these blazed piles are a type of marker pile and that the knoll is a marker pile site. Here was something very significant: all the piles were visible from the top of the knoll and the ones further down the slope were larger, as if to ensure their visibility from the top. This video, although I am a bit confused about the directions I am reporting, is critical:


See how everything is visible from the top? So this now becomes a hypothesis about marker pile sites: the piles are placed so as to be viewed from a point above. This is an important idea and I have more to report because it was nicely exemplified again later in the weekend.